The monitoring network within this area

Hydrionis holds 418 values from 5 gauges within it. Discharge is a property of a gauge and its reach, not of this drainage area, so this page reports the network and its records rather than a single figure.

5
Gauges
418
Values held
1929–2025
Record spans
Gauges within the Upper Dan huc8 subbasin
5 monitoring points, positioned as the publisher records them.
Gauges within the Upper Dan huc8 subbasinDAN RIVER NEAR FRANCISCO, NC, MAYO RIVER NEAR PRICE, NC, SANDY RIVER NEAR DANVILLE, VA, NORTH MAYO RIVER NEAR SPENCER, VA, SMITH RIVER AT MARTINSVILLE, VADAN RIVER NEAR FRANCISCO, NCMAYO RIVER NEAR PRICE, NCSANDY RIVER NEAR DANVILLE, VANORTH MAYO RIVER NEAR SPENCER, VASMITH RIVER AT MARTINSVILLE, VA

Every gauge Hydrionis holds within this area

Gauges within the Upper Dan and what each holds
GaugeMeasuresValuesRecord
SANDY RIVER NEAR DANVILLE, VAmean river flow951930–2024
NORTH MAYO RIVER NEAR SPENCER, VAmean river flow941929–2024
DAN RIVER NEAR FRANCISCO, NCmean river flow821938–2025
SMITH RIVER AT MARTINSVILLE, VAmean river flow741951–2024
MAYO RIVER NEAR PRICE, NCmean river flow731930–2025

How these gauges were attached to this water

Assigned by the publisher to a numbered basin Every gauge here is assigned to this drainage area by its own publisher, which issues the area an official code — 03010103. A drainage area is not a river: it contains the tributaries as well as the main channel, and a gauge in it may be on any of them.

What each gauge’s link to this water rests on
GaugeEvidenceEstablished
SANDY RIVER NEAR DANVILLE, VAStated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/42026-08-26
NORTH MAYO RIVER NEAR SPENCER, VAStated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/42026-08-26
DAN RIVER NEAR FRANCISCO, NCStated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/42026-08-26
SMITH RIVER AT MARTINSVILLE, VAStated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/42026-08-26
MAYO RIVER NEAR PRICE, NCStated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/42026-08-26

What this record holds

Hydrionis decides which waters get a page, and which of those are offered to search, from what is actually held rather than from how the page reads. Five signals are counted; this record has 2 of them, which makes it a profile, not indexed.

Information-gain signals held for this water body
SignalHeldCounts
Gauges holding a real record5yes, 3 or more
Years spanned97yes, 20 or more
Values held418no
Distinct measurements1no
Publishers measuring it1no
Official identifiers1recorded, not counted

Where these figures come from

Spatially aggregatedHigh confidence2024

Source: USGSNational Water Information System, USGS site 02074500, parameter 00060, annual mean statistics. Licence: Open.

Method: Annual mean discharge as published by the USGS statistics service, computed by USGS from its own quality-controlled daily record. Hydrionis converts cubic feet per second to cubic metres per second and records the publisher unit alongside; it does not recompute the mean.

Data from the U.S. Geological Survey National Water Information System, a work of the United States government and therefore in the public domain.

Retrieved 24 August 2026.